Data Sources

Data sources provide the underlying data for table definitions. They handle filtering, sorting, and pagination operations while abstracting away the specific data storage mechanism.

Each table definition must specify a data source to fetch its data from.

Available Data Sources

Custom table definitions

Use these when you are building your own table view with a TableDefinition.

Data Source	Description
DatabaseDataSource	SQLAlchemy queries — the standard choice for production tables backed by the database.
ListDataSource	In-memory list of dicts — ideal for small datasets, demos, and tests.

Resource preview (automatic)

These data sources are used automatically by the Resource View feature to preview uploaded or linked resources. You generally do not need to instantiate them directly.

Data Source	Triggered by format	Description
CsvUrlDataSource	csv	Reads CSV files with auto-detected delimiter.
XlsxUrlDataSource	xlsx	Reads the first sheet of an Excel workbook.
OrcUrlDataSource	orc	Reads Apache ORC columnar files.
ParquetUrlDataSource	parquet	Reads Apache Parquet columnar files.
FeatherUrlDataSource	feather	Reads Apache Arrow Feather files.
DataStoreDataSource	any (when datastore_active)	Queries the CKAN Datastore API directly — no caching.